BaiKiemTra1

data(iris) # Doc du lieu iris co san trong R
quartiles <- quantile(iris$Sepal.Length)# Tinh cac tu phan vi cua Sepal.Length
quartiles# In ket qua

##   0%  25%  50%  75% 100% 
##  4.3  5.1  5.8  6.4  7.9

library(ggplot2)# Nap thu vien ggplot2
# Ve boxplot
ggplot(iris, aes(x = Species, y = Petal.Length, fill = Species)) +
  geom_boxplot() +
  labs(
    title = "Boxplot Petal.Length theo tung nhom Species",
    x = "Species",
    y = "Petal.Length"
  ) +
  theme_minimal()

#Câu2

import pandas as pd

# 1. Doc file iris.csv
# Gia su file iris.csv nam cung thu muc voi file Rmd
try:
    df = pd.read_csv("iris.csv")
    print("Da doc file iris.csv thanh cong.")
except FileNotFoundError:
    print("Khong tim thay file iris.csv. Su dung du lieu mau de demo.")

    # Tao du lieu mau
    data = {
        "Species": [
            "Setosa", "Setosa",
            "Versicolor", "Versicolor",
            "Virginica", "Virginica"
        ],
        "Sepal.Width": [3.5, 3.0, 2.7, 2.9, 3.1, 3.0]
    }

    df = pd.DataFrame(data)

## Da doc file iris.csv thanh cong.

# 2. Tinh trung binh, lon nhat, nho nhat cua Sepal.Width theo Species
result = (
    df.groupby("Species")["Sepal.Width"]
      .agg(["mean", "max", "min"])
)

# 3. Doi ten cot cho de hieu
result = result.rename(columns={
    "mean": "Trung_binh",
    "max": "Lon_nhat",
    "min": "Nho_nhat"
})

print("\nKet qua thong ke:")

## 
## Ket qua thong ke:

print(result)

##             Trung_binh  Lon_nhat  Nho_nhat
## Species                                   
## setosa           3.428       4.4       2.3
## versicolor       2.770       3.4       2.0
## virginica        2.974       3.8       2.2

# 4. Xuat ket qua ra file CSV
result.to_csv("species_summary.csv")
print("\nDa xuat file species_summary.csv thanh cong.")

## 
## Da xuat file species_summary.csv thanh cong.